The review I posted on Audiogon at the end of November 2008 generated a gratifying amount of interest in the Keces 151 Mk1. An unexpected benefit was some lively discussions on boards and some private messages offering me the chance to compare my impressions with other owners.

Based on the first review and some additional feedback, David Wei was kind enough to offer me the opportunity to review the new Keces 131 Mk2 and the Keces 151 Mk2. As of February 2009 these are the production models. In addition David sent along the new PT-111 300w isolation transformer with a single duplex, and a new power cable the IeGO L80520.

The new components - including the transformer - share the same sleek WAF friendly black case with Plexiglas top as the 151 Mk1. The PCBs and wiring are done to a very high standard.

The Keces 131 Mk2 is a SPDIF/Toslink DAC that uses the Burr Brown PCM1793 chip. It is capable of decoding 24/192.

Like the original 151, the Keces 151 Mk2 is a USB DAC that uses the Burr Brown PCM2702 chip.

The131 and 151 use the same op amp, power supply circuit, transformer, almost the same chassis, and the same or similar components. David explained that the other differences are DAC specific.

I noticed that the new 151 board is slightly larger and that the two coupling caps have been eliminated. Both the 131 Mk2 and the 151 Mk2 now use a fully DC coupled signal path – bypassing their inevitable coloration and added expense. In addition the op-amp voltage has been raised from 12v to 15v.

All in all, this is a substantial set of upgrades to a very new product line – remarkably Keces has been able to hold the price.

At my request, David upgraded both review units with the beautifully finished silver IEC inlets. These are described as neutral with improved dynamics. This puts the Keces 131 Mk2 at US$440 plus shipping. And the Keces 151 Mk2 at US$340 plus shipping.

For my test set up, I used my Macintosh G5 PPC, with a dedicated 500Gb SATA drive for my iTunes Library. All my music is ripped as Apple Lossless.

To connect the 151, I used my Opticis USB cable with a battery power supply. To connect the 131, I used my Wireworld SuperNova 5 Toslink. I no longer own a premium SPDIF cable so I was not able to compare the SPDIF and Toslink inputs.

I plugged the PT-111 isolation transformer into the wall using the IeGO L80520 cable. The cable is a specially drawn high purity silver over copper that has been cryogenically treated. It is a stiff cable, beautifully finished in Techflex and sporting IeGO cryo'ed copper male and female plugs. Cosmetically it is a departure from the other cables I have gotten from David. I found it a bit stiff to use with a light DAC.

I plugged the DACs into the Keces PT-111 transformer using another IeGO cable with rhodium plated copper plugs and an Oyaide Tunami cable. At 300w it’s a slick solution for someone who wants clean power in a small space or wants to separate their digital front end from the rest of their rig.

As a general note, I found that these DACs are sensitive to power and power cabling. This is consistent with many of the DACs on the market today. Each DAC had well over a 150 hours on it before any critical listening took place.

The DACs are connected to a NuForce IA-7 V2 – a 100w integrated amp. The NuForce is very fast, handles dynamics effortlessly and throws a wide soundstage.

For speakers I have a pair of Meadowlark HotRod Kestrels that have been upgraded with Cardas binding posts, Mundorf Silver In Oil Caps, Duelund resistors and rewired with Mundorf Silver/Gold wire to the tweeters and Duelund copper to the woofers. The Peerless tweeters are a wide dispersion design so placement is forgiving and the sweet spot generous. They are connected to the amp via Chimera speaker cables.

The room is 12x16 and heavily treated both with a variety of diffusers as well as wall-to-wall carpet and furniture. As you might expect the system is capable of glorious timber and inner detail. I am especially fond of tenor sax, clarinet and cello – as well as female vocals - at which this combination excels.

With all this technical description out of the way, let’s get on to the music.

Let me start with a few general observations since in many ways these units are more similar then not. Both units are very quiet. And both are very musical. The music is cohesive and flows. Instruments are precisely placed. I find that both are very rich, with a warm, slightly dark quality that I am coming to think of as the Keces house sound.

In comparison to the 151Mk1, the 151 Mk2 is a marked improvement, especially on the low end. Over time I had found the 151 Mk1 to be somewhat boomy and not always resolving low-end details.

In fairness, my system was undergoing a considerable revamp during that time on its way to its present incarnation. But I have corresponded with a number of people who shared the same impression. The Mk2 has a tighter low end and offers up considerably more detail throughout.

David will be the first to tell you that he considers the 131 to be the better sounding unit of the two. Also the 131 can receive and decode 24/192. I did not have any high rez material to test this. (Note this is not an upsampling unit.)

Using Diana Krall’s “Departure Bay” I preferred the 131. Each instrument was better defined with more air around it. Placement is more precise. The sound stage extended past the speakers. Her voice is placed well in front with her breathing and decay more pronounced. The soft brushwork separated cleanly from the piano and the bass.

I asked my SO in the room to listen to a couple of cuts. First I played the old standard by Getz & Gilberto, “The Girl From Ipanema”. Christine much preferred the 131. She pointed to the reediness of the sax; the more distinctive brush sound, the better left/right balance (always a problem with this cut) and felt that the voice had more resonance. She opined that the 131 was well worth the hundred-dollar premium.

She asked if she could hear “Blue Rondo A La Turk” from Dave Brubeck’s legendary “Take Five”. This time Christine much preferred the 151. She felt that with the 151 the sound filled the room. The piano and percussion were fuller, the decay longer.

I preferred the 131. We agreed that with the 131 the cowbells and cymbals were better defined and sounded more metallic. For me the greater separation between piano, bass and drums helped to reveal the inner workings of the composition, especially the interplay between bass and piano. And I preferred the rounder tone on Desmond’s alto.

I wanted us to listen to a modern recording and picked the celebrated Mapleshade Recording of “Almost Blue” by Kendra Shank on After Glow. This is an intimate, live recording with a deep soundstage that was recorded direct to tape without EQ or reverb.

Again Christine preferred the 151. She pointed to the fuller sound, and noted that she heard more detail in the percussion. Significantly she pointed to the blending of the voice and the piano; noting that with the 131 the voice sounded naked, almost as if it was overdubbed over the piano.

Again I preferred the 131 for its additional detail, and what I felt was a more direct connection with the singer and the song.

Christine’s reactions points out the conundrum. No matter which Keces I put in the system (including the original 151), I enjoy the sound in my room. I was never aware of any deficiencies or found anything lacking. It is only when one starts comparing units that differences become discernible.

I don’t find anything surprising about this. What I do find remarkable is how satisfying each unit is in it’s own right.

Hello,Thanks for the review of these two Keces DACs. Please advise if you made a direct comparison with the Valab. If so, what are your impressions? Also, which version of the Valab do you have as I understant their newest 2009 model has a new board and better performance.

Thanks for your response. I have not tried the Keces DACs but they were among my initial candidates. However, after settling in with the Valab (Dec 08), I found it may not be needed anymore. Then came the 2009 model with the new board. I have a unit burning in and will give it a shot soon. Head-fi.org has a trail of comparison notes between the two and it appears to be a worthwhile upgrade with the latest version.